21-letter words containing a, f, e, r
- caroline of brunswick — 1768–1821, wife of George IV of the United Kingdom: tried for adultery (1820)
- catherine of braganza — 1638–1705, wife of Charles II of England, daughter of John IV of Portugal
- cause-effect graphing — (programming) A testing technique that aids in selecting, in a systematic way, a high-yield set of test cases that logically relates causes to effects to produce test cases. It has a beneficial side effect in pointing out incompleteness and ambiguities in specifications.
- certificate authority — (cryptography, body) (CA or "Trusted Third Party") An entity (typically a company) that issues digital certificates to other entities (organisations or individuals) to allow them to prove their identity to others. A Certificate Authority might be an external company such as VeriSign that offers digital certificate services or they might be an internal organisation such as a corporate MIS department. The Certificate Authority's chief function is to verify the identity of entities and issue digital certificates attesting to that identity. The process uses public key cryptography to create a "network of trust". If I want to prove my identity to you, I ask a CA (who you trust to have verified my identity) to encrypt a hash of my signed key with their private key. Then you can use the CA's public key to decrypt the hash and compare it with a hash you calculate yourself. Hashes are used to decrease the amount of data that needs to be transmitted. The hash function must be cryptographically strong, e.g. MD5.
- certificate of origin — a document stating the name of the country that produced a specified shipment of goods: often required before importation of goods
- charterhouse of parma — a novel (1839) by Stendhal.
- chief master sergeant — a solider of the highest enlisted rank in the US Air Force
- chief warrant officer — a senior-ranking warrant officer in various armed forces
- circle of declination — hour circle.
- clearance certificate — permission for a ship to use, leave, or enter a port
- clement of alexandria — Saint. original name Titus Flavius Clemens. ?150–?215 ad, Greek Christian theologian: head of the catechetical school at Alexandria; teacher of Origen. Feast day: Dec 5
- college of propaganda — information, ideas, or rumors deliberately spread widely to help or harm a person, group, movement, institution, nation, etc.
- collimator viewfinder — a type of viewfinder in a camera
- collins street farmer — a businessman who invests in farms, land, etc
- comfortably-furnished — containing comfortable furniture
- commercial fertilizer — fertilizer manufactured chemically, as distinguished from natural fertilizer, as manure.
- conference facilities — Conference facilities are large rooms and pieces of equipment that a hotel provides so an organization can have conference there.
- confirm a reservation — If you confirm a reservation, you inform someone who has booked a room at a hotel that the reservation is definite.
- conspiracy of silence — If there is a conspiracy of silence about something, people who know about it have agreed that they will not talk publicly about it, although it would probably be a good thing if people in general knew about it.
- continental breakfast — A continental breakfast is breakfast that consists of food such as bread, butter, jam, and a hot drink. There is no cooked food.
- correctional facility — A correctional facility is a prison or similar institution.
- cosmological redshift — the part of the redshift of celestial objects resulting from the expansion of the universe.
- court of common pleas — (formerly) a superior court exercising jurisdiction in civil actions between private citizens
- credit life insurance — insurance guaranteeing payment of the unpaid portion of a loan if the debtor should die.
- customer satisfaction — When customers are pleased with the goods or services they have bought, you can refer to customer satisfaction.
- dark-field microscope — ultramicroscope
- dataflow architecture — a means of arranging computer data processing in which operations are governed by the data present and the processing it requires rather than by a prewritten program that awaits data to be processed
- dead from the neck up — stupid or unintelligent
- defender of the faith — the title conferred upon Henry VIII by Pope Leo X in 1521 in recognition of the King's pamphlet attacking Luther's doctrines and retained by subsequent monarchs of England
- degradation of energy — the principle that during any irreversible process the total energy available to do work decreases.
- delusions of grandeur — If someone has delusions of grandeur, they think and behave as if they are much more important or powerful than they really are.
- department of defense — the department of the U.S. federal government charged with ensuring that the military capacity of the U.S. is adequate to safeguard the national security. Abbreviation: DOD.
- department of justice — the department of the U.S. federal government charged with the responsibility for the enforcement of federal laws. Abbreviation: DOJ.
- detoxification centre — a place that specializes in the treatment of alcoholism or drug addiction
- dictionary definition — the meaning of a word as given in a dictionary or dictionaries
- differential analyzer — an analog computer designed for solving certain differential equations.
- differential calculus — the branch of mathematics that deals with differentials and derivatives.
- differential equation — an equation involving differentials or derivatives.
- differential geometry — the branch of mathematics that deals with the application of the principles of differential and integral calculus to the study of curves and surfaces.
- differential operator — a function, usually expressed as a polynomial, that indicates linear combinations of the derivatives of the expression on which it operates.
- differential quotient — derivative (def 6).
- differential topology — the branch of topology that studies the properties of differentiable manifolds that remain invariant under diffeomorphisms.
- differential windlass — a pair of hoisting drums of different diameter turning at the same rate, such that a pulley suspended below them on a line wound on the larger drum and unwound from the smaller drum is raised with mechanical advantage.
- differential-quotient — something that has been derived.
- draft once reuse many — (jargon) (DORUM) Reusing parts of a document to produce parts of an entirely new document. The term normally refers to text documents but the practise is equally common in programming.
- drop the handkerchief — a children's game in which all the players but one stand in a circle facing inward, while that one player stealthily drops a handkerchief behind a player in the circle who must pursue and attempt to catch the one who dropped the handkerchief before the latter reaches the vacated place.
- dumfries and galloway — a region in S Scotland. 2460 sq. mi. (6371 sq. km).
- dwarf japanese quince — a low, shrubby, Japanese flowering quince, Chaenomeles japonica, of the rose family, having salmon-to-orange flowers and yellow fruit.
- electromagnetic field — a field of force associated with a moving electric charge equivalent to an electric field and a magnetic field at right angles to each other and to the direction of propagation
- ethics of the fathers — a treatise of the Mishnah that comprises six chapters and consists chiefly of proverbs, aphorisms, and principles of ethics, law, and religion.